Flexible coated abrasive product



July 12,1938. H. o. ANDERSON FLEXIBLE COATED ABHASIVE PRODUCT Filed Aug.15, 1956 HARRY -D. ANDEkslJ/v Patented July 12, 19 38 REISSUED JUL 15194i i T OFFICE FLEXIBLE COATED ABRASIVE PRODUCT Harry 0. Anderson,Worcester, Mass, assignor to Norton Company, Worcester, Mass., acorporation of Massachusetts Application August 15, 1936, Serial No.96,205

3 Claims.

The invention relates to flexible coated abrasive products.

One object of the invention is to provide a coated abrasive which may bereadily crumpled up and which is convenient to use. Another object ofthe invention is to provide a coated abrasive of open structure withfine grain. Another object of the invention is to provide a free cuttingcoated abrasive product. Another object of the invention is to provide acoated abrasive for rubbing down articles having irregular surfacecontours. Another object of the invention is to provide a coatedabrasive product particularly useful for furniture finishing and thelike. Another object of the invention is to provide an open meshabrasive cloth particularly useful for household purposes such as thescouring of pans. Another object of the invention is to provide a coatedabrasive product to do work now to some extent done 20 by steel wool andarticles known as Chore Boys. Other objects will be in part obvious orin part pointed out hereinafter.

The invention accordingly consists in the fea-' tures of construction,combinations of elements, and arrangements of parts, as will beexemplified in the structure to be hereinafter described, and the scopeof the application of which will be indicated in the following claims.

In the accompanying drawing,

Figure 1 is a diagrammatic view showing one of many possiblearrangements of apparatus for the manufacture of the flexible coatedabrasive product of the invention;

Figure 2 is a plan view of one embodiment of the product of theinvention onan enlarged scale;

Figure 3 is a cross sectional view-of the embodiment of Figure 2; and

Figure 4 is a view similar to Figure 3 showing in longitudinal section amodification of the invention.

Referring first to Figure 1, I provide a roll IU of leno cloth. Lenocloth is woven cloth in which the warp is divided into pairs of ends andwhen the shed is changed, one end of each pair is moved over and acrossthe other end of each pair. Thus, instead of the warp ends being one upand one down, alternately, as in a plain weave, they are in twistedrelation to each other. Leno cloth is well understood and bolting clothand similar fabrics as well as curtains are made therefrom. I prefer touse leno cloth made from cotton warp and weft. I prefer to use a plainleno cloth. The characteristic of leno cloth which is of particularimportance so far as the present invention is concerned is that theweave produces an open mesh material and furthermore the open characterof the weave is maintained during use of the material. In other wordsthere is much less tendency of the warp to run together and bunch, or ofthe weft to do the same, than in the case of a cheese cloth, 5 forexample. A cheese cloth is a. cloth with the warp and weft spaced so asto make an open structure but made with a plain weave. So far as certainfeatures of the invention are concerned I might use a cheese cloth orany open mesh cloth whether made with a plain weave or not, but I preferto use the leno cloth in some form. So far as certain features of theinvention are concerned it may be embodied in knitted goods but thetendency to stretch and to pull outof shape of such goods is such that Iprefer to use woven goods embodied in leno cloth as aforesaid.

I provide apparatus which may include suitable supports or standards,not shown, supporting a plurality of rolls and a grain hopper, excessgrain receivers and adhesive or bond containers, which supports orstandards are not shown as the mounting of the various elementsdisclosed may be carried out in any suitable manner and is wellunderstood in the coated abrasive art. Considering therefore thediagrammatic view of Figure 1, I provide a roller I I and a roller l2overwhich the sheet 13 of leno cloth is drawn. 1 provide further areceptacle M for a suitable adhesive, which may be heated if desired. Aroller l5 extends below the level of the liquid in the container 14 andtherefore coats'the sheet l3 with the adhesive. Any known or desiredadhesive may be used. For example any one of the various glues may beemployed or any one .of the waterproof binders including thosecontaining the drying, non-drying, and semi-drying oils, and also suchbinders as incorporate any one of the resins either natural orartificial. For example, shellac or a varnish may be used or on theother hand a synthetic resin product may be employer I further provide apressure roller l6 around which the sheet l3 extends. By reason of theopen structure of the leno sheet 13 it will be coated with adhesive notmerely on one side but on both sides.

I provide an abrasive grain hopper i'l. This may be filled with abrasivegrain 18 of any desired type, for example fused alumina otherwise knownas aluminum oxide abrasive, emery, corundum, silicon carbide, garnet,quartz, sand, or even diamond bort. The abrasive grain 68 in the hopperl I may be delivered by the roller l9 located in the bottom of thehopper.

I provide a roller 20, a roller 2|, a roller 22, and f a roller 23. Ipass the sheet l3 first over the roller 20 then back over the roller 2|then over the roller 22 then back over the roller 23 as shown. I providea receptacle 24 for surplus grain. I provide rollers 25 and 26 and leadthe sheet l3 under these and then over a roller 21 and thence into adrying chamber 28. This drying chamber may take any usual or desiredform and the sheet I3 may be disposed therein in festoons according tothe usual practice.

Considering now the deposit of the abrasive grain l8, it lands on what Iarbitrarily term the upper side of the sheet l3 of leno cloth and someof it adheres to the upper side of the warp or the weft thereof. Somealso adheres to the sides of the warp and the weft of the leno cloth andis therefore located in the interstices of the' fabric. Stating this inanother way, there is a geometrical space between the one surface of thefabric and the other surface of the fabric which is of measurableproportions and some of the abrasive grain is between these planes.

Some of the grain, however, passes through the openings in the lenocloth and this lands on What I term the .back side of the cloth after ithas passed over the roll 20. The back side of the warp and weft istherefore coated with abrasive grain and some more attaches itself tothe cloth in between the planes aforesaid and exists in the intersticesof the cloth. However, some of the grain passes through the cloth asecond time and this falls on the upper side of the cloth after it haspassed around the roller 2i. Such of the abrasive grain as passesthrough the cloth a third time lands on the back side thereof after thecloth has passed around the roller 22. By thus passing the abrasivegrain through the cloth four times it receives and retains as muchthereof as can be held in place by the binder employed; the remainderfalls into the receptacle 24.

After the cloth has passed through the drying chamber 28 the abrasivegrain is stuck to it. It

now passes over a roller 30 then down around a roller 3| and under aroller 32 then upwardly to a roller 33 and then in contact with a roller34 which extends into liquid adhesive in a receptacle 36. This liquidadhesive may be what is common ly, referred to as a sizing coat. Thesheet l3 now goes around a pressure roller 31 over a roller 38 to asecond drying chamber 40 where the material may also be festooned.Thence the sheet 13 goes over a roller 4| and to a take-up roll 42 ofthe finished product.

Considering now a modification of the invention, I may provide a roll 45of paper the width of which is substantially the same as the width ofthe sheet l3. This is arranged in such position that the sheet 46 ofpaper may pass over the roller 33 in contact with the sheet i3 and byreason of the sizing coat it will adhere to the sheet l3 and form abacking for the sheet l3. When using the roll 45 of paper I prefer tothread the sheet l3 so that it shall not pass four times below thehopper I! but rather pass over the roller 20 then under the roller 22and then over the roller 21 as shown in dotted lines in Figure 1. Thus,according to this embodiment of the invention, only one side and theinsterstices of the sheet 3 is coated with abrasive grains. Any otherexpedient may be adopted for this purpose, for example the use of asuitable baffle or shield plate.

Considering now the product of the invention, Figures 2 and 3 disclosethe embodimeit where no backing sheet 46 is employed. The leno clothconsists of pairs 50 and 5| of warp ends twisted on each other at eachpick together with a plurality of weft threads 52 passing between pairsof warp ends 50 and 5|. Abrasive grain I8 is stuck to the warp and weftas shown and remains on both sides of each warp end, and on both sidesof each weft thread or pick, and in the interstices between warp andweft as shown in Figures 2 and 3. It will be observed that theindividual abrasive granules are shown as smaller in diameter than thewarp or the weft. Leno cloth is preferably made with warp of lessdiameter than the weft in so much as there are two ends of warp twistedtogether and if the usual or preferred square arrangement as shown inFigure 2 is to be achieved there will be twice as many warp ends asthere are weft threads. Stating this in another manner, preferably thepick is one half the sley thus making the openings square and in orderthat the actual weight of yarn in the warp and weft shall be the same,the count of the warp ends is twice that of the weft. I prefer that theabrasive grain shall be smaller in diameter than the diameter of thewarp in order that good adhesion may be secured and in order to avoid acondition in which the abrasive grains too readily become detached fromthe fabric. For example, using s warp and 40s weft, I prefer to useabrasive grain as fine as 400 mesh size and I prefer to produce a fabricof the order of 20 picks per inch and of sley 40 ends to the inch.However, the invention has no limits in this respect; leno cloth of only10 picks to the inch or even less may be employed if desired, and on theother hand, especially if very fine grain is used, for example 600 to1000 grit size, leno cloth of 50 to picks per inch or even finer may beemployed.

Considering now the embodiment of Figure 4, paper 46 of a thickness thesame as or less than that of the sheet l3 will preferably be employed.Any type of paper may be used within the limits of the invention andfurthermore for the sheet 46 of paper I may substitute cloth with aclose weave. Cloth with a plain weave but with the warp and weft closetogether, or cloth with any fancy weave in which the warp and weft areclose together is quite distinct and different from leno cloth. Cottoncloth of such nature cannot be seen through and furthermore abrasivegrain will not pass into it or through it. Ordinary paper is alsoimpervious to abrasive grain as is well understood. Therefore theembodiment of Figure 4, even where cloth is used, represents twodistinct types of fabric with abrasive grain stuck to one of them and ofsuch a nature that an open abrasive structure is produced yet in whichthe individual granules are relatively fine. Such an abrasive structurehas characteristics that are quite distinct and individual. It is freecutting and at the same time cutting lines are exceedingly fine.

The product of Figure 2 and Figure 3 may be crumpled and used to polishor abrade any irregular shaped article. It can be efficiently used forthe scouring of pots and pans. Whereas a coated abrasive product such asis generally referred to as sandpaper resists being crushed into a balland even then presents non-abrading portions and flat portions, theproduct of the invention can be rolled into almost any shape and isalmost plastic. If a waterproof binder is used it is especially usefulfor abrading articles under water or with water.

The article of Figure 4 has distinct characteristics. The paper Mi may,if desired, be waterproof paper so that the coated abrasive product ofFigure 4 may be used under water or wet. It has an open very freecutting structure and at the same time the abrasive grains are of smallsize.

These characteristics produce a cutting action unlike that of anyheretofore known product.

Whereas a cotton leno cloth has been specifically referred to, it shouldbe understood that other yarns may be employed. Furthermore theapparatus described is exemplary only and any other suitable apparatusor coating method may be employed. For example, the electrostatic methodof coating now well known in actual practice may be used if desired. Itwill thus be seen that there has been provided by this invention anarticle in which the various objects hereinabove set forth together withmany thoroughly practical advantages are successfully achieved. As manypossible embodiments may be made of the above invention and as manychanges might be made in the embodiment above set forth, it

is to be understood that all matter hereinbeforeset forth, or shown inthe accompanying drawing, is to be interpreted as illustrative and notin a limiting sense.

I claim:

1. A coated abrasive product comprising warp and weft woven into an openmesh leno weave cloth, an adhesive, and a quantity of abrasive grainsome of which is smaller in diameter than the diameter of the weft, theabrasive grain being stuck to the leno cloth by the adhesive on at leastone surface of the leno cloth and some of the abrasive grain being stuckto the warp and weft and being between the surfaces of the leno cloth,substantially all'of the grain projecting from the adhesive and beingfree from adhesive on its outside portions away from the warp and weftrespectively.

2. A coated abrasive product comprising warp and weft woven into an openmesh leno cloth, an adhesive, and a quantity of abrasive grain some ofwhich is smaller in diameter than the diameter of the weft, the abrasivegrain being stuck to the leno cloth by the adhesive on both surfaces ofthe cloth and some of the abrasive grain being stuck to the warp andWeft and being between the surfaces of the cloth, substantially all ofthe grain projecting from the adhesive and being free from adhesive onits outside portions away from the warp and weft respectively.

3. A coated abrasive product comprising warp and weft woven into an openmesh leno weave cloth, a quantity of abrasive grain some of which issmaller in diameter than the diameter of the "weft, an adhesive securingsuch abrasive grain to the leno cloth, a backing impervious to theabrasive grain, and an adhesive securing the leno cloth to the backing,substantially all of the grain projecting from the adhesive and beingfree from adhesive on its outside portions away from the warp and weftrespectively.

' HARRY O. ANDERSON.

